Terminal connecting members or mounts are often used for affixing or physically securing very small diameter magnet wires to terminal leads or power wires, which typically are relatively heavy or large diameter, in the assembly or manufacture of certain electric devices such as electrical coils. The terminal connecting means in such devices are a prime cause or source of rejects or product failure because of very high incidence of breakage of the fine diameter magnet wire at or adjacent the terminal connection, and/or because of dislocation of the terminal means with the wires attached thereto.
For instance, in a typical encapsulated potential coil, the very fine magnet wire of the coil, for example, about 0.0045 of an inch in diameter, is extended to and applied with several loops around a terminal member or mount, such as the conventional prior art terminal member shown in the drawing, for connection with a lead or wire supplying energizing electrical power. The relatively larger terminal lead or power wire, illustrated in the drawing, is superimposed over the applied loops of the fine magnet wire around the terminal member to thereby make electrical contact, and the thus arranged wires or conductors are permanently affixed or physically secured to each other and the terminal member by soldering, or other appropriate electrical connecting means.
In addition to the relatively fragile nature of wire of such fine diameter as the magnet wire commonly used in coils and other electrical devices, one common type of conventional prior art terminal member, such as illustrated in the drawing, is produced by stamping the unit from sheet metal stock. Such prior terminal members which are formed by stamping have edges which are rough and irregular, and frequently contain burrs, undulations and sharp portions. Thus, the fine, fragile magnet wire looped around the terminal member is very easily severed by any sharp or irregular surface or edge portions, and is particularly subject to breakage when pulled taut or otherwise in contact therewith under force.
Moreover, this potential or occurrence of breakage of the fine magnet wire resulting from its severance by the terminal member is very often increased by an encapsulation procedure. The application of an encapsulating plastic dielectric coating or covering on the coil by means of a hot thermoplastic melt frequently introduces or increases tension in, or creates other detrimental physical forces upon the portion of the magnet wire leading to and/or looped around the terminal member, or upon the terminal member itself with the wire affixed thereon.
For instance, the viscosity of such molten encapsulating materials is frequently relatively high and rapidly increases with the fast rate of cooling due to the heat sink effect of the metal coil or other device undergoing encapsulation, or other rapid temperature reducing influences. Thus, the encapsulating operation or materials tend to introduce or accentuate tension or compression forces acting upon the fine magnet wire, and/or upon the terminal member with the wires affixed thereto with the likely movement or dislocation of the overall terminal, carrying the wires with it. Additionally, a dislocated terminal member, due to a failure of its positioning and/or securing means, can result in faulty or insufficient encapsulation or coating of the entire device, including the wires or terminal member.